1. Field of the Invention
The present invention is directed to an apparatus for withdrawing a predetermined or selected box from a flow of folded boxes traveling in a plane in a device.
2. Prior Art
In a box folding and gluing machine, the box blanks being processed into folded boxes generally belong to one and the same batch. However, on account of handling errors, there is a possibility that box blanks of identical shape and size but with different printing might be either added to or mixed with the box blanks of the batch being processed by the folding and gluing machine. An example of the problem, which will occur from such an error, is that for instance a given batch of box blanks, which are to be folded and glued into folded boxes, might have printing in French and contain blanks having the printing in English, German or some other language. Thus, the whole batch of folded and glued boxes must be sorted before being sent to the customer to ensure that they all contain the printing in the correct language. Since sorting is a manual process, it takes a lot of time and is expensive.
Another problem that occurs in box folding and gluing machines is ensuring that each box is actually glued. Experience has shown that insufficient gluing of the box may be either due to inadequate application of the glue by the gluing unit of the machine or due to the box having a damaged or torn off glue flap so that the box is not provided with the necessary glue and is therefore not usable. In order to spot insufficiently glued boxes after they travel through a box folding and gluing device, it is necessary to sort the boxes, which are collected at the machine's outlet.
To solve the above mentioned problems and to avoid sorting, various solutions have already been proposed. One of these solutions consist in providing the box blanks with a code corresponding to the information printed thereon and this code will indicate the type of lettering, color and graphic display on the box. By scanning this code and comparing it with the code for the particular box blank that is to be utilized, a blank or box having either the wrong color, graphic representation, or lettering can be rejected.
One of the devices which has been proposed for rejecting and undesired box utilizes a rotating disk operating jointly with an intermittenly actuated pressure roll. In the box folding and gluing machine, this device is located at an outlet of a section which is equipped with means for accelerating and ejecting folded and glued boxes and, therefore, is immediately before the device which counts the boxes. In this particular section, the folded boxes are carried between a lower and upper continuous belt conveyor. The device for ejecting the undesired box box is situated outside of the lower conveyor with the upper plane of the rotating disk coinciding with the plane formed by the lower side of the folded and glued box being transported on the conveyors. The pressure roll is positioned obliquely with regard to the direction of travel of the boxes so that when it is actuated, it will engage the undesired box and cause it to move sideways relative to the flow of boxes in the conveyor.
The operation of this device has certain inconveniences, for example, it compels the operator of the machine to pull the undesired box sideways from between the bells of the upper and lower conveyors. Thus, it will be necessary to release the pressure applied by the belts of the conveyor in the area where the undesired box is to be rejected. The lack of pressure on the boxes provides certain handicaps such as causing the conveyance of the boxes to be less reliable and interferring with the counting of the box blanks. In folding and gluing apparatuses, the boxes are counted up to the nth box, which is shifted sidewise in the conveyor. The sidewise shifting of the nth box is obtained by kicking or striking an edge of the nth box so that it will be knocked against a target or stop, which is situated on an opposite side of the conveyor to the kicking or striking device. If the box is held positively between the belts of the upper and lower conveyors, its sidewise shift will correspond practically to the distance existing between the box edge before the shift and the target. However, if on the other hand, the box is not held properly, for example the upper conveyor applies an insufficient pressure on the box, the box will rebound from the target or stop and in the worst case, the box counted and kicked will practically return to its former position. In such an instance, it is almost impossible to distinguish at the outlet of the machine which box actually represents the nth box.
Another difficulty is that if a large size box is to be rejected, the pulling out of the box from between the belts of the upper and lower conveyor will possibly cause the belts to be driven or pulled off of their respective pulleys or belt sheaves.